1. Field of the Invention
The present invention relates to an interchangeable drum unit interchange system, which makes it possible to quickly and systematically interchange a plurality of interchangeable drum units in an interchangeable drum type rotary printing machine installation.
2. Description of the Prior Art
In an interchangeable drum type rotary printing machine installations, the time necessary for the work of interchanging a plurality of interchangeable drum units occupies a great part in a printing process.
The interchange operation of interchangeable drum units in the prior art has involved such working process that a skilled worker draws a used interchangeable drum unit out of a printing machine, carries it up to an interchangeable drum unit set table while loading on an interchange truck, places the used interchangeable drum unit on the set table, subsequently transfers a new interchangeable drum unit to be used in the next printing work from the interchangeable drum unit set table to the interchange truck to carry it up to the printing machine, and mounts the new interchangeable drum unit to the printing machine. In the case where such interchange work is carried out for a plirality of interchangeable drum units, the work would necessitate a lot of time and labor.
In general, with regard to a variety of the interchangeable drum units, there are known the single-drum interchange type in which only a plate drum for use in typographic printing, number printing, etc. is interchanged, two-drum interchange type in which a pair of plate drums and press drums in typographic printing or a pair of plate drums and blanket drums in offset or dry offset are interchanged, three-drum interchange type in which a set of plate drums blanket drums, and press drums in offset or dry offset are interchanged, and further four-drum interchange type in which a set of upper plate drums, upper blanket drums, lower blanket drums and lower plate drums are interchanged in offset or dry offset for simultaneously printing both upper and lower surfaces.
Among the above-described respective types of the interchangeable drum units, in the case of the three-drum interchange type or the four-drum interchange type, depending upon the sizes of the drums, the weight could become heavier than 1 ton, and require heavy labor and become dangerous work for a worker to draw out these drums onto a truck by hands and to carry them between the interchangeable drum unit set table and the printing machine.
Especially, in the case of the four-drum interchange type, the weight becomes about 2 tons and exceeds the range of manual work by a worker. In addition, it is obvious that the interchange time would be remarkably increased due to handling of heavy drum units.